The proposed project will investigate the hypothesis that cell to cell electrical coupling which occurs in the crystalline lens of the eye is essential to the long-term maintenance of its transparency. Junctional and surface membrane resistance properties will be investigated using conventional microelectrode current passing and voltage recording techniques. The results will be interpreted using mathematical considerations developed to describe current flow and voltage changes in a spherical cell. Changes in the junctional and surface membrane properties will be sought after the formation of experimental cataracts in animals, and following the perfusion of lenses in vitro with known cataractogenic compounds. Electron and light microscopic techniques will be utilized to investigate the morphologic changes occurring in each type of cataract created. Of particular importance will be the electron microscopic study of the morphometrics relating to junctional complexes in the lens. Electron microprobe techniques will be used to localize calcium in normal and cataractous lenses.